As illustrated in U.S. Pat. No. 4,577,927, dark field illumination of gems has long been known as a technique for evaluating the gem and determining defects or inclusions. Such patent which is in the name of the present inventor has a viewing lens formed as part of the end of a flashlight body and when the lens is open to a 90.degree. position provides for such dark field illumination.
U.S. Pat. No. 2,178,371 to Eichenberger shows a combination flashlight and magnifying glass for reading, for example, gas or electric meters; the magnifying glass may be flipped up and the gas meter read. Here, compared to the above Raney patent, there is no dark field illumination. The magnifying lens, however, is attached by a rather complex retrofit to the flashlight including a split resilient band and a ring in which it is retained. In other words, significant modification of the flashlight must be made.